The biochemistry core unit will serve to: a. provide information by using HPLC to measure XO, XD and GSH/GSSF in plasma and tissue samples from the various protocols in this proposal. This approach guarantees quality, efficiency and economy in these sophisticated approaches. b. help each project with measurement of 02 metabolites or elastase produced by neutrophils or other factors. These include assays of 02, H202, H0C1, OH, oxidized antiproteases, AMT inactivation of catalase, H202 scavenging, SOD and catalase and other approaches. c. develop special techniques for assessing 02 metabolites in bitro and in biological systems. Our previous studies have been on the development of assays for XO and XD, GSH/GSSG in plasma and RBC, as well as DMTU/DMSO consumption and product formation. We are particularly interested in more convincingly documenting the effect of 02 metabolite and elastase mediated lung and kidney injury by better measurement approaches. This unit will be directed by Natalie B. Parker, Ph.D., and experienced biochemist, who is dedicated to the accurate conduct of these and other techniques which will prove necessary to multiple sections of the grant during the course of the investigations. Natalie Parker will also help a number of the other investigators who are working o various aspects of 02 metabolite or elastase measurement (e.g. Mark Simchuk, Project Six, Parsons and Stephan Velasco, Project Five, Harken).